DE 198 31 574 A1 describes a seat heater comprising an electrical surface heating element made of woven carbon filaments, which surface heating element is used as a flexible resistance material to which along a border region of the surface heating element main electrodes for heating the surface heating element are connected. In order to achieve a shorter heating-up period the seat heater comprises an additional device with electrodes that extend over a partial region of the surface heating element.
DE 10 2004 042 423 A1 describes an aerodynamic component with surface heating for the prevention of ice formation on an exterior surface of the component.
Furthermore, from DE 10 2004 031 625 A1 a circuit arrangement for the diagnosis of heating resistance is known in order to determine a heating temperature.
EP 0 745 919 A1 describes a method for controlling the temperature of a heating element. During the measuring phase, heating is interrupted and the resistance of the heating element is compared to the setpoint setting. Depending on whether the resistance of the heating element is below the setpoint value, the control system for the alternating-voltage switch is informed as to whether or not heating needs to take place in order to reach the setpoint value.
WO2007/107732 A1 describes a system for the prevention of ice formation, which system is designed in such a manner that the heating devices used are kept at a constant temperature.
From U.S. Pat. No. 5,824,996 an electrically conductive textile heating element is known that comprises ribbons that are woven from non-metallic yarns. In this arrangement the ribbons are laid in their longitudinal direction onto a substrate component.
From US 2006/0278631 A1 the use of a woven material in ribbon form or nonwoven material structures is known for the production of an electrically conductive textile heating element, which woven material or nonwoven material structures are bonded onto a substrate in a previously prepared mould.
DE 101 51 298 A1 describes a heating foil on a substrate material in which resistance wires have been integrated along preferential directions.
Furthermore, from the general state of the art a method for the production of a heating body is known, in which method an electrically conductive carbon fibre layer is vapour-deposited onto a substrate material.
U.S. Pat. No. 6,137,083 describes a heating layer on an aerodynamic component for heating an elongated region of said aerodynamic component. The heating layer comprises a woven fabric in which bundles of electrically conductive rovings and insulation fibres that separate said rovings from each other are woven together with weft threads that extend transversally to the aforesaid and in the direction of the weft so as to support the woven fabric. The heating layer has been applied to a surface of the aerodynamic component in such a manner that the bundles of rovings extend parallel to each other along the front edge of the component. Such a woven material is associated with a disadvantage in the case of large-area implementations, in that in these cases, during the production process, the woven fabric overall needs to be stabilised with the use of binder material. The binder material has a negative effect on the material characteristics such as stiffness and strength or on the fatigue characteristics of the heating layer. These characteristics are, in particular, of great importance in applications relating to aircraft construction in order to form stable aerodynamic components with long service lives.
DE 42 14 636 A1 describes a multi-axial reinforcement structure comprising at least one sheet-like substrate layer and reinforcement threads, associated with this substrate layer, which at least in some regions extend along the lines of force corresponding to the tensions occurring in the moulded part.